v3.26.1
Debt (Component of Debt-Footnotes) (Details)
€ in Millions, $ in Millions
Jun. 30, 2026
EUR (€)
Jun. 30, 2026
USD ($)
Feb. 28, 2026
EUR (€)
Feb. 28, 2026
USD ($)
Jan. 31, 2026
EUR (€)
Jan. 31, 2026
USD ($)
Dec. 31, 2025
USD ($)
Debt Instrument [Line Items]              
Weighted average interest rate 5.14% 5.14%          
Unused borrowing capacity, amount   $ 827.5          
Deferred liabilities   400.7         $ 423.4
Carrying amount   8,343.1         8,584.8
Long-term Debt              
Debt Instrument [Line Items]              
Estimated fair value   8,300.0         8,600.0
Trade accounts receivable              
Debt Instrument [Line Items]              
Secured debt   $ 204.4         228.4
Aggregate Variable and Fixed Rate Indebtedness              
Debt Instrument [Line Items]              
Weighted average interest rate 3.81% 3.81%          
Telenet Credit Facility              
Debt Instrument [Line Items]              
Weighted average interest rate 5.27% 5.27%          
Carrying amount   $ 4,577.8         4,748.0
Telenet Credit Facility | Sunrise Holding Revolving Facility              
Debt Instrument [Line Items]              
Unused borrowing capacity, amount € 625.0 713.4          
Telenet Revolving Facility I              
Debt Instrument [Line Items]              
Unused borrowing capacity, amount 580.0   € 550.0 $ 627.8      
Telenet Revolving Facility I | Revolving Credit Facility              
Debt Instrument [Line Items]              
Borrowings repaid         € 90.0 $ 102.7  
Telenet Revolving Credit Facility B              
Debt Instrument [Line Items]              
Unused borrowing capacity, amount   662.1          
Telenet Overdraft Facility              
Debt Instrument [Line Items]              
Unused borrowing capacity, amount 25.0 28.5          
Telenet Revolving Facility              
Debt Instrument [Line Items]              
Unused borrowing capacity, amount € 20.0 $ 22.8          
VM Ireland Credit Facility              
Debt Instrument [Line Items]              
Weighted average interest rate 5.70% 5.70%          
Unused borrowing capacity, amount € 100.0 $ 114.1          
Carrying amount   1,027.3         1,056.2
VM Ireland Credit Facility | Sunrise Holding Revolving Facility              
Debt Instrument [Line Items]              
Unused borrowing capacity, amount € 100.0 114.1          
Egg Power Capex Facility | Secured Debt              
Debt Instrument [Line Items]              
Carrying amount   78.4         19.8
Formula E              
Debt Instrument [Line Items]              
Secured debt   $ 57.1         $ 58.7